I also hear this, sounds very faint, a little bit clearer with headphones.

If I can go on another tangent I would just like to recommend Octonauts. It is charming, funny and clever show. My 5 year old daughter loves it and she would like to have a Tweak costume.

I can't stand many kid shows, but this one even I can love. It is incredible for me how Octonauts are not pretentious, like so many "science!" shows for kids are.

I would recommend it for children also. My kids have learned a decent amount from having watched it, unlike many other shows without any real educational content.